2 Corinthians 4:15

15.For all things are for your sakes He now associates himself with the Corinthians, not merely in the hope of future blessedness, but also in these very afflictions, in which they might seem to differ from him most widely, for he lets them know, that, if he is afflicted, it is for their benefit. Hence it follows, that there was good reason why they should transfer part of them to themselves. What Paul states, depends first of all on that secret fellowship, which the members of Christ have with one another, but chiefly on that mutual connection and relationship, which required more especially to be manifested among them. Now this admonition was fraught with great utility to the Corinthians, and brought with it choice consolation. For what consolation there is in this — that while God, sparing our weakness, deals with us more gently, those that are endowed with more distinguished excellence, are afflicted for the common advantage of all! They were also admonished, that, since they could not aid Paul otherwise, they should, at least, help him by their prayers and sympathy.

That the grace which hath abounded. That agreement (489) between the members of Christ he now commends on the ground of the fruit that springs from it — its tendency to advance the glory of God. By a metonymy, according to his usual manner, he means, by the term grace, that blessing of deliverance, of which he had made mention previously — that,

while he was weighed down, he was, nevertheless, not in anxiety: while oppressed with poverty, he was not left destitute, etc.,
(2 Corinthians 4:8,)

and in fine, that he had a deliverance continually afforded him from every kind of evil (490) This grace, he says, overflows. By this he means, that it was not confined to himself personally, so that he alone enjoys it, but it extends itself farther — namely, to the Corinthians, to whom it was of great advantage. When he makes the overflowing of God’s gift consist in gratitude, tending to the glory of its Author, he admonishes us, that every blessing that God confers upon us perishes through our carelessness, if we are not prompt and active in rendering thanks.